Metal abundances in extremely distant Galactic old open clusters. II. Berkeley 22 and Berkeley 66

Abstract

We report on high resolution spectroscopy of four giant stars in the Galactic old open clusters Berkeley~22 and Berkeley~66 obtained with HIRES at the Keck telescope. We find that $[Fe/H]=-0.32\pm 0.19$ and $[Fe/H]=-0.48\pm 0.24$ for Berkeley~22 and Berkeley~66, respectively. Based on these data, we first revise the fundamental parameters of the clusters, and then discuss them in the context of the Galactic disk radial abundance gradient. We found that both clusters nicely obey the most updated estimate of the slope of the gradient from \citet{fri02} and are genuine Galactic disk objects.

20 pages, 6 eps figures, accepted for publication in the Astronomical Journal

References in corpus (4)

• Evolutionary tracks and isochrones for low- and intermediate-mass stars: from 0.15 to 7 M_sun, and from Z=0.0004 to 0.03
• Abundances for Globular Cluster Giants: I. Homogeneous Metallicities for 24 Clusters
• Metal abundances in extremely distant Galactic old open clusters. I. Berkeley 29 and Saurer 1
• Berkeley 22, an old and distant open cluster towards the Galactic anticentre

Cited by in corpus (22)

• Chemical abundance analysis of the Open Clusters Cr110, NGC2099 (M37), NGC2420, NGC7789 and M67 (NGC2682)
• On the fine structure of the Cepheid metallicity gradient in the Galactic thin disk
• The evolution of the Galactic metallicity gradient from high-resolution spectroscopy of open clusters
• Elemental Abundance Ratios in Stars of the Outer Galactic Disk. IV. A New Sample of Open Clusters
• NGC 6791: an exotic open cluster or the nucleus of a tidally disrupted galaxy?
• Old open clusters in the outer Galactic disk
• Chemical abundance analysis of the Open Clusters Berkeley 32, NGC 752, Hyades and Praesepe
• A Chemical Abundance Study of 10 Open Clusters Based on WIYN-Hydra Spectroscopy
• The Bologna Open Cluster Chemical Evolution (BOCCE) Project: midterm results from the photometric sample
• On the metallicity of open clusters II. Spectroscopy
• Open clusters as key tracers of Galactic chemical evolution. III. Element abundances in Berkeley 20, Berkeley 29, Collinder 261, and Melotte 66
• Abundances of four open clusters from solar stars
• The Gaia-ESO survey: Calibrating a relationship between Age and the [C/N] abundance ratio with open clusters
• Abundances and kinematics for ten anticentre open clusters
• A photometric study of the old open clusters Berkeley 73, Berkeley 75 and Berkeley 25
• Evidence of Early Enrichment of the Galactic Disk by Large-Scale Winds
• Chemical abundance analysis of the old, rich open cluster Trumpler 20
• Blue Straggler Stars in Galactic Open Clusters and the effect of field star contamination
• Radial Velocities of Three Poorly Studied Clusters and the Kinematics of Open Clusters
• Photometric and spectroscopic study of the intermediate-age open cluster NGC 2355
• Old open clusters and the Galactic metallicity gradient: Berkeley 20, Berkeley 66, and Tombaugh 2
• Old open clusters as key tracers of Galactic chemical evolution. I. Fe abundances in NGC 2660, NGC 3960, and Berkeley 32